Expose GLES2Interface to blink, and delete isContextLost() from WGC3D.

third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h

Index: third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h
diff --git a/third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h b/third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h
index c71432d7c43a1ec4c0b998967d1cbbfbf4f37cd5..e7f987c39d54ac1121a6d28f6fe5b7e66272815f 100644
--- a/third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h
+++ b/third_party/WebKit/public/platform/WebGraphicsContext3DProvider.h
@@ -35,6 +35,12 @@
 
 class GrContext;
 
+namespace gpu {
+namespace gles2 {
+class GLES2Interface;
+}
+}
+
 namespace blink {
 
 class WebGraphicsContext3D;
@@ -45,6 +51,7 @@ public:
 
     virtual WebGraphicsContext3D* context3d() = 0;
     virtual GrContext* grContext() = 0;
+    virtual gpu::gles2::GLES2Interface* getGLInterface() = 0;
 };
 
 } // namespace blink